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All Journal HAYATI Journal of Biosciences Natural Science: Journal of Science and Technology Biospecies Journal of Tropical Life Science : International Journal of Theoretical, Experimental, and Applied Life Sciences Jurnal Pendidikan Matematika dan IPA AL KAUNIYAH Biogenesis: Jurnal Ilmiah Biologi Jurnal Biologi Universitas Andalas Indonesian Journal of Biotechnology JMPM (Jurnal Material dan Proses Manufaktur) Jurnal Penelitian Pendidikan IPA (JPPIPA) Jurnal Biologi Tropis JURNAL KESEHATAN PERINTIS Majalah Kedokteran Andalas Menara Ilmu International Journal of Agricultural Sciences Jurnal Pembelajaran dan Biologi Nukleus Sainstek : Jurnal Sains dan Teknologi Best Journal (Biology Education, Sains and Technology) Jurnal Ners Journal of Ocean, Mechanical and Aerospace -science and engineering- (JOMAse) Makara Journal of Science
Djong Hon Tjong
Universitas Andalas
Aerospace Engineering Agriculture, Biological Sciences & Forestry Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Chemistry Computer Science & IT Decision Sciences, Operations Research & Management Earth & Planetary Sciences Economics, Econometrics & Finance Education Engineering Environmental Science Health Professions Immunology & microbiology Industrial & Manufacturing Engineering Languange, Linguistic, Communication & Media Materials Science & Nanotechnology Mathematics Mechanical Engineering Medicine & Pharmacology Nursing Physics Public Health Social Sciences Other

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Elimination of ineffective inorganic salt component in medium for indole‐3‐acetic acid synthesis by Serratia plymuthica UBCF_13 and its effect on the growth of chili seedlings Liza Aulia Yusfi; Djong Hon Tjong; Irawati Chaniago; Muhamad Irsyad; Jamsari Jamsari
Indonesian Journal of Biotechnology Vol 29, No 2 (2024)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/ijbiotech.88774

Abstract

Indole‐3‐acetic acid (IAA) is an essential phytohormone that controls a variety of plant growth mechanisms. Bacteria can produce IAA to stimulate plant growth, with its production influenced by the culture conditions. Serratia plymuthica UBCF_13 is recognized as an IAA‐producing bacterium, exhibiting maximum IAA production in a yeast medium comprising yeast extract, sucrose, K2HPO4, MgSO4, NaCl, and CaCO3. However, prior studies optimizing individual inorganic salt components indicated minimal impact on IAA synthesis within this medium. This study aimed to eliminate the unnecessary inorganic salt components and the medium was then applied to investigate the IAA biosynthesis pathway and the plant growth‐promoting assay. The elimination assay consisted of yeast sucrose medium devoid of K2HPO4, MgSO4, NaCl, or CaCO3, and yeast sucrose medium containing only MgSO4 and CaCO3. Various indole compounds were then added to the revised medium composition to investigate the IAA biosynthesis pathway of UBCF_13 using high‐performance liquid chromatography (HPLC). Furthermore, the effect of UBCF_13 culture supernatant, cultivated in the new medium, on chili plant growth was evaluated. The highest IAA production (138.8 µg/mL) was observed in the yeast sucrose with CaCO3 and MgSO4 (elimination of K2HPO4 and NaCl). The presence of indole‐3‐acetamide (IAM) compound from the medium extracts, supplemented with multiple indole compounds, revealed that UBCF_13 may use the IAM pathway. The application of UBCF_13 supernatant enhanced the shoot, root length, fresh weight, and germination time of chili seeds by 37.7%, 49.3%, 204.3%, and 38.6%, respectively. This study demonstrated that eliminating K2HPO4 and NaCl provided a new culture medium composition conducive to IAA production by UBCF_13. Moreover, the UBCF_13 extract has the potential to promote plant growth.
HUBUNGAN FILOGENETIK SPESIES LIMNONECTES (RANIDAE: AMPHIBIA) ASAL SUMATERA BARAT DAN ASAL ASIA TENGGARA BERDASARKAN GEN 16S RIBOSOMAL RNA Tjong, Djong Hon; Iskandar, Djoko T.; Gusman, David
Makara Journal of Science Vol. 14, No. 1
Publisher : UI Scholars Hub

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

Phylogentic Relationship among Limnonectes (Ranidae: Amphibia) found in West Sumatra with Other Species from South East Asia based on the based on the 16S rRNA Gen. The objective of this research was to study the phylogenetic relationship among Limnonectes species found in West Sumatra and with other species from South East Asia based on the partial DNA sequences16S rRNA sequences. DNA sequences were aligned using ClustalX version 1.64b, and the phylogenetic relationship within samples were analyzed using PHYLIP version 3.5c program. The alignment showed that, from 805 sites, there are 250 parsimony informative polymorphism sites. The phylogenetic tree showed that all of the Limnonectes spesies were divided in two clusters, the L. blythii complex and L. kuhlii complex. L. kuhlii and L. sp1 clustered into L. kuhlii complex and L. shomponerum and L. macrodon were clustered to L. blythii complex. This result showed that L. kuhlii and L. blythii are species complexes that are actually constituted of several species.
Regeneration of Cattleya Amazing Thailand in ½ MS Medium with The Addition of Several Concentration of PGR and Coconut Water Asnul Fitria; Zozy Aneloi Noli; Djong Hon Tjong
Jurnal Biologi Tropis Vol. 23 No. 2 (2023): Special Issue
Publisher : Biology Education Study Program, Faculty of Teacher Training and Education, University of Mataram, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29303/jbt.v23i2.6067

Abstract

One of the Cattleya species with aesthetic and commercial value is Cattleya Amazing Thailand. An efficient protocol with a high rate of plantlet regeneration is through in vitro culture. Plantlet regeneration is affected by the addition of a Plant Growth Regulator (PGR). Auxin and cytokinin (2,4-D and BAP) combined with PGR from organic material such as coconut water can increase the growth of leave and roots in plantlet regeneration. The research aims to determine the best PGRs combination in regenerating the  Cattleya Amazing Thailand orchid in vitro. The research used the Completely Randomized Design (CRD) experimental method for five treatments. The parameter are survival rate, number of leave, and number of roots. Survival rate was analyzed descriptively and both of number of leave and roots were analyzed statistically. All treatments can form 100% plantlets on survival rate parameter. The treatment of 0.1 mg/L 2,4-D + 1 mg/L BAP gave significantly different results in the number of leaf (9.0) and was not significantly different in the number of root. 0.1 mg/L 2,4-D + 1 mg/L BAP is the best combination for in vitro regeneration of the Cattleya Amazing Thailand orchid. 
Authentication of Barbonymus spp. From Lake Singkarak Using DNA Barcoding: Authentication of Barbonymus spp. From Lake Singkarak using DNA Barcoding Salis, Viola Mutiara; Roesma, Dewi Imelda; Tjong, Djong Hon; Syaifullah; Aadrean; Dahelmi
Journal of Tropical Life Science Vol. 14 No. 3 (2024)
Publisher : Journal of Tropical Life Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.11594/jtls.14.03.15

Abstract

The local community distinguishes between Barbonymus belinka (Balingka) and Barbonymus schwanefeldii (Kapiek) in Lake Singkarak based on size due to the morphological similarities between the two species. From previous reports, B. belinka (Balingka) is a fish endemic to Lake Singkarak, West Sumatra, while B. schwanefeldii has a wider distribution, including Sumatra, Kalimantan, and Java. Consequently, molecular identification is necessary to discern between the species and to understand the DNA barcode characteristics of fish belonging to the genus Barbonymus in Lake Singkarak. One molecular technique utilized for species identification is DNA barcoding, which focuses on the COI (Cytochrome Oxidase Subunit I) gene. Liver tissue samples from Balingka and Kapiek fish from Lake Singkarak were used in the study. Based on 585 bp of COI gene sequences and 30 comparison sequences from BOLD system and GenBank NCBI, seven samples from Lake Singkarak show a genetic distance of 0–1.2% from B. schwanefeldii populations elsewhere, with 15 differing nucleotide bases. Moreover, samples from Lake Singkarak show a genetic distance of 7.7–8.2% from B. belinka in the BOLD system from Aceh, with 42 differing nucleotide bases. Furthermore, two specific bases are present in B. schwanefeldii from Lake Singkarak. Based on the results of this research, it is known that all samples from Lake Singkarak, including Balingka and Kapiek, belong to the same species, namely B. schwanefeldii.
Hydroxyapatite Bilayers Coating on Screw Implant Ti6Al4V ELI with Electrophoretic Deposition Method for Improving Osseointegration Juliadmi, Dian; Oktaviana, Dili; Tjong, Djong Hon; Manjas, Menkher; Gunawarman, Gunawarman
Journal of Ocean, Mechanical and Aerospace -science and engineering- Vol 51 No 1 (2018): Journal of Ocean, Mechanical and Aerospace -science and engineering- (JOMAse)
Publisher : International Society of Ocean, Mechanical and Aerospace -scientists and engineers- (ISOMAse)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.36842/jomase.v51i1.42

Abstract

Utilization of an alloy titanium (particularly Ti6Al4V), as fracture fixation in biomedical application has restriction because of will associate with osseointegration failure. An effort to titanium coating by hydroxyapatite monolayer still has poor mechanical properties and may lead to implantation failure. Hydroxyapatite bilayers coating aims to protect releasing hazardous ions from implant to the body and improving the osseointegration at the same time. In this research, nanoparticle hydroxyapatite (first layers) and microparticle hydroxyapatite (second layers) were used as coating materials on implant prototype of Ti6Al4V ELI screws. The coating was carried out by electrophoretic deposition (EPD) method used different voltage (2 and 3 volt) for deposition time of 2 and 3 minutes for forming first layers. The process was then continuing for making second layer at 5 and 10 volt for 2 and 5 minutes. In order to intensify of coatings, hydroxyapatite bilayers-coated titanium was air-dried overnight and then sintered at 700oC for 1 hour. The coating layers were characterized by optical microscope, Scanning Electron Microscope (SEM) and thickness gauge series tester. Result of the study show that nanoparticle hydroxyapatite layers are more uniform, thin, dense than microparticle hydroxyapatite layer. Moreover, the second layer shows less adhesion. The obtained voltage and deposition time for best bilayers coating characteristic are 2 volt/3 minutes for nanoparticles hydroxyapatite and 5volt/5minutes for microparticles hydroxyapatite. By approximately 71%-100% surface coverage and 56µm thickness of bilayers coating, that parameters can be considered to improve osseointegration.
Hydroxyapatite Coating on New Type Titanium, TNTZ, Using Electrophoretic Deposition Nuswantoro, Nuzul Ficky; Maulana, Imron; Tjong, Djong Hon; Manjas, Menkher; Gunawarman, Gunawarman
Journal of Ocean, Mechanical and Aerospace -science and engineering- Vol 56 No 1 (2018): Journal of Ocean, Mechanical and Aerospace -science and engineering- (JOMAse)
Publisher : International Society of Ocean, Mechanical and Aerospace -scientists and engineers- (ISOMAse)

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (147.205 KB) | DOI: 10.36842/jomase.v56i1.37

Abstract

In order to improve bioactivity of new type of titanium alloy, TNTZ, Hydroxyapatite (HA) coating is applied. Electrophoretic Deposition (EPD) has chosen as coating method because the simplicity of the instrument and its making, inexpensive cost, and ability to coat things with complicated design. EPD used electric current to move the HA particle through electrode in the suspension of ethanol and HA. Desired HA coating quality can be adjusted with optimizing the voltage and coating time. This research aimed to analyzed the effect of voltage and coating time of EPD process toward the HA coating that produced on the surface of new type titanium implant prototype, Ti-29Nb-13Ta-4.6Zr (TNTZ). Voltages are in range of 3, 5, and 7 volt and coating times are in range of 3, 5, and 7 minutes. Based on the result it is known that the best HA coating that can be produced are on 7 minutes and 7 volt. This best result shows the good surface morphology, highest value of screw mass growth, coating thickness, and surface coverage. Enhancement of voltage will affect the surface coverage value of HA coating, however, coating time will affect the thickness. Based on this research it can be concluded that enhancement of the voltage can produced HA coating that spread more evenly that proved by the increasing of surface coverage value. The enhancement of coating time will produce thicker layer of HA coating and increase deposition rate of HA on the implant surface. This result shows that the EPD can be used to produce TNTZ titanium implant that coated with HA for orthopedic application.
DNA Barcoding and eDNA Metabarcoding for Identification Species: A Case Study (West Sumatra): DNA barcoding and eDNA metabarcoding Roesma, Dewi Imelda; Tjong, Djong Hon; Syaifullah, Syaifullah; Nofrita, Nofrita; Janra, Muhammad Nazri; Aidil, Dyta Rabbani; Prawira, Furqan Dwiki Lintang; Salis, Viola Mutiara
Journal of Tropical Life Science Vol. 15 No. 1 (2025)
Publisher : Journal of Tropical Life Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.11594/

Abstract

The biodiversity of freshwater fish is important to study because there is data and information that remain undiscovered. The waters of Sumatra, especially West Sumatra, are areas with high freshwater fish diversity but have limited information. Providing information and genetic data has become one of the important things to conduct. DNA barcoding and eDNA metabarcoding have become molecular methods for identifying species and providing information about the presence of species in a region. A study using DNA barcoding and eDNA metabarcoding was conducted on freshwater fish in several locations in West Sumatra. Isolation and amplification of DNA were performed directly on individual samples and sequenced using conventional methods (Sanger sequencing) to generate DNA barcodes. Water samples were collected (2 liters) at each location using a sterile bottle. The water samples were filtrated, isolated, and amplified using universal primer and sequenced with next-generation sequencing techniques. The study successfully collected 25 species belonging to 14 genera, 2 families, and 1 order. A total of 134 sequences from West Sumatra with a length of 648-670 bp were analyzed. All DNA barcodes were submitted to the BOLD System and GenBank, NCBI. The mean Kimura two-parameter model (K2P) genetic distances within species, genera, families, and orders were 0.7%, 8.3%, 15.8%, and 21.3%, respectively. The eDNA metabarcoding technique has successfully detected three native fish species in the waters of West Sumatra (Barbonymus schwanefeldii, Mystacoleucus padangensis, and Rasbora jacobsoni). The availability of fish DNA barcodes in reference databases is crucial for the success of identification using eDNA metabarcoding. Combining identification using conventional methods and eDNA metabarcoding can provide more reliable results and become a reference for future freshwater monitoring.
EXPLORATION OF INDIGENOUS BACTERIA WITH POTENTIAL FOR TOTAL AMMONIA NITROGEN DEGRADATION FROM RUBBER WASTEWATER AND PHYLOGENETIC TREE CONSTRUCTION BASED ON 16S rRNA GENE SEQUENCES Melinda, Annisa; Febria, Fuji Astuti; Tjong, Djong Hon
Jurnal Pendidikan Matematika dan IPA Vol 16, No 3 (2025): September 2025
Publisher : Universitas Tanjungpura

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26418/jpmipa.v16i3.93436

Abstract

Rubber wastewater contains total ammonia nitrogen (TAN) at levels that can potentially cause pollution if discharged into water bodies without proper treatment. TAN content is one of the commonly used parameters for assessing water quality. Certain groups of bacteria are capable of naturally degrading TAN in the environment. This study aimed to isolate bacteria from rubber wastewater, evaluate their potential to degrade TAN, and identify the most effective isolate at the molecular level. Samples were collected from wastewater treatment ponds using random purposive sampling based on specific criteria. A survey method was used to determine sampling locations, while experimental methods were applied in the laboratory. Bacterial isolation was conducted using the serial dilution technique, followed by inoculation with the pour plate technique. Pure isolates were obtained using the streak plate technique. The degradation potential of the bacterial isolates was tested by inoculating 10% v/v of each isolate into 200 mL of rubber wastewater, followed by incubation at room temperature for six days. TAN levels were analyzed using the phenate method with a spectrophotometer, following the Indonesian National Standard SNI 06-6989.30-2005. Three bacterial isolates (NS-1, NS-2, and NB-1) were obtained from the rubber wastewater. All three isolates demonstrated potential in reducing TAN levels, with final TAN concentrations after incubation ranging from 6.75 to 4.8 mg/L, corresponding to a reduction of 52.50"“66.90%. The most effective isolate in reducing TAN was NS-2. Molecular identification using the PCR-seq method of the 16S rRNA gene revealed that isolate NS-2 showed 99.86"“99.93% sequence identity with Enterobacter sp. This study provides a basis for the development of bioremediation technologies for rubber wastewater treatment to improve aquatic environmental quality.
EXPLORATION OF INDIGENOUS LEAD (PB)-RESISTANT BACTERIA FROM RUBBER WASTEWATER AS CANDIDATES FOR BIOREMEDIATION AGENTS Putri, Emilya; Febria, Fuji Astuti; Tjong, Djong Hon
Jurnal Pendidikan Matematika dan IPA Vol 16, No 3 (2025): September 2025
Publisher : Universitas Tanjungpura

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26418/jpmipa.v16i3.93437

Abstract

The presence of heavy metals such as lead (Pb) in rubber processing wastewater originates from coagulant materials, vulcanization processes, and raw water contamination. Pb is toxic and persistent, thus requiring proper treatment. This study aims to isolate indigenous bacteria from rubber wastewater that are resistant to Pb and have potential as bioremediation agents. Isolation was performed using the dilution-pour plate method, with selection on a medium containing Pb(NO₃)â‚‚. Resistance tests were conducted at increasing concentrations (100"“350 ppm). Three isolates (IS-1, IS-2, IS-3) were obtained, with IS-3 exhibiting the best growth (μ = 0.641 day⁻ ¹; generation time (G) 1.08 days). Molecular identification of the best bacterial isolate revealed that IS-3 is Pseudomonas protegens. This isolate shows potential as a bioremediation agent for Pb contamination.
Deteksi crypstosporidium sp. pada pasien dengan kanker kolorektal Handayani, Sri Wahyuni; Irawati, Nuzulia; Tjong, Djong Hon; Tofrizal, Tofrizal; Firdamila, Elli
Majalah Kedokteran Andalas Vol. 48 No. 3 (2025): MKA July 2025
Publisher : Faculty of Medicine, Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/mka.v48.i3.p299-308.2025

Abstract

Cryptosporidium sp. adalah parasit obligat intraseluler yang menyerang sel epitel usus. Infeksinya mengakibatkan diare, malnutrisi, dehidrasi dan cedera usus terutama pada orang dengan gangguan imunitas. Tingginya infeksi Cryptosporidium pada pasien HIV-AIDS pada penelitian  sebelumnya menandakan sumber infeksi yang tinggi di lingkungan. Cryptosporidium dilaporkan memiliki hubungan dengan kanker kolorektal baru-baru ini. Tujuan: tujuan penelitian ini adalah untuk mengetahui prevalensi infeksi Cryptosporidium pada pasien dengan kanker kolorektal. Metode: metode yang digunakan observasional dengan desain cross-sectional study pada 43 pasien kanker kolorektal yang sesuai dengan kriteria yaitu pasien yang baru didiagnosis dan belum mendapatkan terapi onkologis. Pengumpulan sampel feses dilakukan dari bulan April hingga Agustus 2023. Pemeriksaan ookista dilakukan secara mikroskopik dengan pewarnaan tahan asam modifikasi ziehl neelsen. Hasil: hasil penelitian didapatkan 46,5% (20/43) pasien positif terinfeksi Cryptosporidium. Kesimpulan: kesimpulan hasil penelitian, infeksi Cryptosporidium tinggi pada pasien kanker kolorektal, terutama pada lokasi kanker rektum. Penelitian lebih lanjut untuk mengetahui spesies Cryptosporidium diperlukan untuk mengetahui  rute penularan dan sumber infeksi.
Co-Authors - Jumawita - Syaifullah . Mansyurdin Aadrean Aidil, Dyta Rabbani Aldino Fauzil Fanani Almurdi Almurdi Amanda Nurhafitri Amir Hamidy AMIR HAMIDY Anggraini, Debie Annisa Farma Annisa Khaira Annisya Fitri Anthoni Agustien Anthonie Agustien Anugrah Viona Agesi Arum Setiawan Asnul Fitria Asrori, Ikrima Aurora, Dhea Apriano Dahelmi Dahelmi Dahelmi David Gusman Dewi Imelda Roesma Dharmayanthi, Anik Budhi Dian Juliadmi Djoko T. Iskandar Djoko T. Iskandar, Djoko T. Dwitya Elvira Dyta Rabbani Aidil Elli Firdamila Endang Purwati RN Essy Harnelly fachrul reza, fachrul Fanny Adhy Putri Fanny Lestari Fauzan . Feskaharny Alamsjah Firdamila, Elli Fuji Astuti Febria G Gunawarman, G Gusman, David Hadi Addaha, Hadi Hadi Kurniawan Henny Herwina Hirowati Ali Hirowati Ali, Hirowati Huda, Nadyatul Khaira Ida Ayu Putu Sri Widnyani Ilhamdi, Ilhamdi Indra Junaidi Zakaria Irawati Chaniago Irvan Fadli Wanda Jamsari Jamsari Janra, Muhammad Nazri Jon Affi, Jon Juliadmi, Dian Kevin Origia Kevin Origia Kharisma Putra Liza Aulia Yusfi M. Idris Mahmudul Hasan Mahmudul Hasan, Mahmudul Marlina Marlina Masayuki Sumida Masayuki Sumida, Masayuki Maulana, Imron Melinda, Annisa Menkher Manjas Meri Wulandari Muhamad Irsyad Muhammad Idris Muhammad Silmi Nelmi Fitria Netty Marusin Netty Marusin Nia Kurniawan Nia Kurniawan Nofrita Nofrita Nofrita Nofrita Nurhafitri, Amanda Nurul Aida Nurvalinda Nurvalinda Nuswantoro, Nuzul Ficky Nuzulia Irawati Oktaviana, Dili Padilla, Putri Rahma Prawira, Furqan Dwiki Lintang Putri, Emilya Rahmadina, Shovinda Ravelino Nesty Resti Rahayu Revis Asra Ridho Hendrikos Rifka Rahmat Riska Mayori Rita Permatasari Rivi Hamdani Rizaldi Rizaldi Rizia Irsa Salis, Viola Mutiara Saputri, Rahmi Agu Silvia Indra Sisca Dwi Yarni Sri Wahyuni Handayani Sri Wahyuni Handayani, Sri Wahyuni Suwirmen, Suwirmen Syaifullah Syaifullah Syaifullah Syaifullah Syaifullah Syamsuardi Syamsuardi Syandri, Hafrijal Takeshi Igawa Takeshi Igawa, Takeshi Tesri Maideliza Tofrizal Wilson Novarino Yarni, Sisca Dwi Yelvita Sari Yeni Gusma Yanti Yuliarni Syafrita Yurike Nova Edlin Zil Fadhillah Rahma Zozy Aneloi Noli Zulkarnain, Alivia